1. Field of the Invention
The present invention relates to an interior finishing panel for a vehicle and a method for producing the same. More particularly, it pertains to insert measures for a fiber reinforcing material.
2. Description of the Prior Art
Generally, an interior finishing panel for a vehicle such as door trims and instrument panels is so constructed that a foam base material such as hard urethane foam is integrally molded on the back side of a facing material. Such an interior finishing panel is known and is disclosed in Japanese Utility Model Laid Open Publication No. 58-92041 and Japanese Patent Publication No. 57-46737 wherein a mat-shaped fiber reinforcing material of glass fiber is inserted into the foam base material for improvement in rigidity.
However, in the above-described interior finishing panel wherein the fiber reinforcing material is inserted into the foam base material, if there is a convex section on a surface of the panel, the fiber reinforcing material set in a mold will get caught between an upper mold element (upper die) and a lower mold element (lower die) of the mold during a molding process and then lift at the back side of the convex section. For this reason, as shown in FIG. 12, at a convex section b of an interior finishing panel a, a fiber reinforcing material d, inserted into a foam base material c, is unevenly distributed in a direction away from a facing material e to form a thick portion g of resin layers between the facing material e and the fiber reinforcing material d.
In the above condition, if a molding material such as hard urethane foam used for molding the foam base material c is fed onto the fiber reinforcing material d, the supply of a molding material is impaired by the fiber reinforcing material d. Therefore, the amount of the molding material corresponding to the volume of the thick portion g will not be fed, resulting in a short supply of the molding material. Owing to this short supply, air is entrapped in the thick portion g, leading to the problem that a void f is most likely to occur.
Accordingly, in the event that the void f occurs between the facing material e and the fiber reinforcing material d, the void expands as the temperature of a vehicle compartment rises during the summer or other similar conditions. Thereafter, the facing material e expands, which spoils the appearance of panels and further leads to peeling of the facing material e. In view of this, it is preferable to prevent the fiber reinforcing material d from being unevenly distributed in a direction away from the facing material e.
In order to avoid such an uneven distribution, there has been proposed one type of interior finishing panel as disclosed in Japanese Patent Laid Open Publication No. 63-99912 wherein a fiber reinforcing material is attached to the back side of a facing material by bonding the fiber reinforcing material to the back side of the facing material during a molding process.
However, in the event of the above interior finishing panel, the bonding process, including the application and drying of adhesives, for bonding the facing material to the fiber reinforcing material is time-consuming. Thus, there arises such a drawback that the whole molding time is considerably lengthened.